Furnace fan bearing



Patented Oct. 2, 1934 UNITED STATES FURNACE FAN BEARING Oscar P. Nystrom, Holland, Mich., assignor to Holland Furnace Company, Holland, Mich., a corporation of Michigan 7 Application November 23, 1931 Serial No. 576,710

1 Claim.

This invention relates to a bearing construction particularly adapted for use in connection with furnace fans.

I have heretofore filed a number of applications relating to warm air distribution to the furnace pipes which lead from a furnace casing, one of whichhas Serial No. 267,667, filed April 5, 1928. In such constructions a fan is mounted to turn about a vertical axis in the upper part of a furnace casing and is driven by an electric motor. The bearing for the fan is supported on the top of the furnace casing, the weight of the fan, its shaft and the driving pulley therefor being sustained by the bearing. 1

The present invention is in part a continuation with respect to the above cited application and with further improvements in the bearing which make it more durable, efficient and entirely capable of withstanding the service to which it is subjected.

It is a primary object and purpose of the present invention to provide a lubricating bearing for the fan shaft, one which holds the shaft in proper vertical position and in which the thrust of the weight is taken care of and in which thebearing is continuously lubricated during the rotative movement of the fan.

Another feature of my invention resides in means for filling the bearing with oil to a predetermined depth, this depth providing optimum operating conditions. Also, this same filling means prevents excessive oil from being poured into the bearing, this feature eliminating the fire hazard which is very real in a bearing of this character. Also, the filling means is located so as to be readily accessible for filling.

Another advantage of my invention resides in the provision and use of a fiber bearing below the revolving sleeve, this serving two functions,

" i first, as a thrust bearing, and, second, it prevents the upper shell.

Other objects and purposes than those stated will be understood from the following description, taken in connection with the accompanying drawing, in which,

Fig. l is a fragmentary elevation, with parts broken away and in section, of the upper part of a furnace equipped with the rotating fan with which the bearing of the present invention is associated.

Fig. 2. is a fragmentary enlarged vertical section through said bearing, and

Fig. 3 is a fragmentary. section of one element of the bearing construction.

Like reference characters refer to like parts in the different figures of the drawing.

Warm air furnaces are constructed conven- 5 tionally with an outside enclosing casing 1 of sheet metal, which encloses the furnace radiator, combustion chamber, firepot and ash pit. From the upper end of the furnace casing warm air pipes, as indicated at. 2, lead to the rooms which are to be heated and to which the warm air is delivered from within the furnace casing. The casing is closed at its upper end in my invention by two conical plates 3 and 4, and below the lower plate 3 a substantially horizontal fan 5, with obliquely positioned blades, is sustained at the lower end of ,a vertical shaft 6 which extends upwardly through openings in the top plates 3 and 4. The plates 3 and 4 are spaced apart providing a heat insulating air space between them.

The fan 5 when it is driven forces the rising warm air within the furnace casing outwardly through the outlet pipes 2. The shaft 6 extends a distance above the upper plate 4 and through the bearing which is the subject matter of the present invention. The bearing in its construc, tion includes an outer cup-like member 7 having vertical sides and open at its upper end. At its lower end feet 8 extend downwardly and outwardly and bear against the upper side of the plate 4 within a reinforcing annular rib 4a, shown in Fig. 2, and the feet are permanently connected, as by stove bolts, to the plate 4 The bottom of the member 7 extends inwardly for a distance and is continued upwardly in an inner sleeve 9, the upper end of which extends a short distance above the upper edges of the outer walls of the member 7 and which is annularly recessed and thinned at its upper end as shown. This outer cup-like member 7 provides a receptacle to contain a 100 quantity of oil, indicated at 10, which is replenished when needed through a pipe 11, threaded through one side of the member 7, and at its outer end having an oil cup 12 normally closed at its upper end into which new oil may be deliv- 105 ered. The level of the oil within the member 7 may reach to a plane substantially that of the upper end of the oil cup 12.

A bearing washer 13 of relative heavy fiber is placed over the inner sleeve 9 and rests upon the 110 bottom of the outer member 7. Over said. inner sleeve 9 the second member of the bearing is placed. Said second member comprises a vertical sleeve 14 which, from its upper end to within a short distance of the upper end of the sleeve 9, is machined so as to closely fit said sleeve 9 yet permit a free relative movement. The sleeve 14 at its lower end is formed with an outwardly extending annular flange 15 the lower side of which is smooth and rides against the upper side of the fiber bearing washer 13. At the upper end of the sleeve 14 an outwardly extending annular ledge 16 is integrally formed which terminates in a downturned annular flange or skirt 17 reaching to and around the outer sides of the upper end of the member 7.

The sleeve 14 has a plurality of openings 18 made through it adjacent its lower end and other openings 19 toward its upper end in the plane where the upper end of the sleeve 9 is decreased in thickness. At the inner side of the sleeve 14 spiral grooves 20 are made around the same leading from the lower to the upper openings whereby the oil at 10 passing through the lower openings 18 may be received in the grooves 20 and on rotation of the sleeve 14 in the proper direction the oil is carried upwardly to lubricate the cylindrical bearing surfaces, and any excess thereof delivered through the open ngs 19 back to the oil supply at 10.

A drive pulley is attached to the upper end of the rotating member of the bearing. It is formed preferably of two fiat circular plates 21 of sheet metal which lie against each other but at their edges are diverged into annular flanges 22 to provide a belt receiving groove around the pulley. The shaft 6 extends centrally through the inner sleeve 9 and at its upper end portion is equipped with a hub 23 having an integral outwardly extending annular flange 24 between which and the ledge lfithe plates 21 are located. Screws 25 pass through the flange 24, through said plates 21 and into the ledge 16 as shown in Fig. 2 to secure the parts together. It is of course understood that at the centers of the plates 21 openings are made for the downwardly extending portion of the hub as illustrated in Fig. 2.

The pulley attached to the shaft 6 is driven by an endless belt 26 which in turn passes around a drive pulley 27 on the shaft 28 of an electric motor 29. The motor may be mounted in various Ways and one way for mounting the same is that shown in Fig. 1, where it is carried at the upper end of a post separate from the furnace casing.

, It is, however, to be understood that the present invention is in no way limited to the manner in which the electric motor which drives the fan is mounted or positioned with reference to the furnace casing.

The bearing described is of a particularly durable and efiicient nature. Its lubrication is completely taken care of. The weight of the fan, shaft 6 and'of the pulley attached to the shaft is transmitted to the sleeve 14 and the flange 15 at its lower end to the fiber washer 13 whereby the thrust bearing surfaces are immersed in lubricating oil at all times with a result of practically no wear on either surface; while the cylindrical surfaces at the inner side of the sleeve 14 and the outer side of the sleeve 9 are completely and automatically supplied with lubricating oil at all times. The construction has proven very practical and satisfactory, is one that is especially durable. The oil is protected against the entrance of dirt or dust by the skirt 17 and the skirt at the same time insures against loss of oil or its escaping from the container thereforlto the upper side of the plate 4 from which it could drain to the furnace casing, which result would be of a wholly detrimental nature.

The invention is defined in the appended claim and is to be considered comprehensive of all forms of structure coming within its scope.

I claim: 7

A bearing of the type described comprising, a cup-like member having an outer wall, a bottom, and an inner vertical sleeve extended upwardly from and integral with said bottom and outer wall, means for supporting said member, a compressible bearing washer located around said sleeve within the member, said washer being formed of heat resisting material and a second member adapted to rotate and bear upon said sleeve and also bear against the washer comprising a second sleeve located over the first sleeve and bearing at its lower end on said washer, and having an outwardly'extending horizontal ledge at its upper end terminating in a downwardly extending annular skirt which extends around and below the plate of the upper end of said outer wall of the first member, said second member also having an upper opening and a lower opening leading to the inner vertical sleeve, means for pumping oil continuously through said openings, means for supplying oil to said cup-like member to a level between said openings, a pulley attached to said second member and hollow means leading from the cup-like member to a point exterior of said pulley for the purpose described.

OSCAR P. NYSTROM. 

